BIS Certification for Rolling Bearings Accessories Dimensions for Locknuts and Locking Devices

A bearing locknut looks like an ordinary nut, but it does a job no ordinary nut can: it holds a bearing - and everything riding on it - precisely positioned on a rotating shaft, against vibration, thrust and thermal cycling, for years. Used with a locking device (typically a tabbed lock washer whose tab folds into a nut slot), the locknut clamps adapter sleeves, withdrawal sleeves and bearings axially. Thread accuracy and face squareness are everything - a locknut whose face wobbles even slightly cocks the bearing and destroys it.

IS 16605 (Part 2):2018, harmonised with ISO 2982-2:2013, standardises the dimensions of these locknuts and locking devices - thread sizes, face dimensions, slot patterns and washer geometry - so they pair correctly with standard sleeves and shafts worldwide. Sold both with sleeve assemblies and separately in vast MRO volumes, they are covered under the Bearing Components and Accessories (Quality Control) Order, 2025 and now require the BIS ISI Mark under IS 16605 (Part 2):2018.

Locknut making is precision thread-cutting at scale, and the buyers - bearing brands, plummer-block OEMs, industrial distributors - will move to ISI-marked stock the moment enforcement starts. Standphill India prepares locknut and lock-washer manufacturers for the Scheme-I audit (thread gauging, face-runout inspection, material records), coordinates testing and filing, and naturally pairs this licence with the IS 16605 (Part 1) sleeve licence for makers who produce the full mounting kit.

BIS-recognized laboratories evaluate bearing locknuts and locking devices against IS 16605 (Part 2):2018 for:

• Thread dimensions & fit - thread form, size and class per IS 16605 (Part 2)
• Face squareness / runout - locknut face perpendicular to thread axis
• Slot & tab geometry - locknut slots and washer tab dimensions for positive locking
• Locking washer dimensions - inner tab, outer tabs and thickness
• Material & hardness - steel grade and properties verification
• Surface & marking - finish and size designation marking

Typical timeline: 4-6 months for Indian manufacturers; 8-14 months for foreign manufacturers (FMCS) - against a 6-month general QCO deadline, start immediately.

• BIS application form (Manakonline)
• Factory registration proof
• MSME / Udyam certificate
• Manufacturing process flow chart
• List of machinery & production equipment
• List of in-house testing equipment (with calibration)
• Raw material grade details & test certificates
• Product range & size designations
• Trademark / brand registration
• AIR appointment (foreign mfr.)
• BIS-recognized lab test report per IS 16605 (Part 2):2018

Standphill India is a global BIS consultancy that handles bearing locknuts and locking devices certification end-to-end - from application and factory-audit preparation to lab testing and licence grant. We serve Indian manufacturers and overseas producers in China, Japan, Germany, the USA, and Korea with complete FMCS and Authorized Indian Representative services. BIS consultancy services all over the world.